Administration of a toxoid confers which type of immunity?

• A. Artificially acquired active immunity
• B. Naturally acquired active immunity
• C. Naturally acquired passive immunity
• D. Artificially acquired passive immunity

Answer: (A)

Toxoid vaccination trains the immune system to recognize and neutralize a bacterial toxin. It uses an inactivated toxin to provoke an immune response without causing disease, so the body produces its own antibodies and forms memory cells. That makes the immunity active, because the body's immune system is actively responding and remembering how to fight the toxin in the future. And it’s artificial because the response is induced by a vaccine, not by natural exposure to the toxin. It’s not naturally acquired, and it’s not passive immunity (which would be receiving antibodies from someone else rather than making them yourself). Examples include vaccines against tetanus and diphtheria.